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Old 03-27-2007, 05:45 AM   #1
SlickWillie
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Wiring for inverter

We purchased a 3.2 cubic foot upright freezer for the fiver. I have a 500 watt (1000 watt surge) inverter that I want to run it on while on the road. Here is what I have calculated. The freezer draws almost 2 amps or around 240 watts. It will approximately double that on start up. The inverter will draw about 10 amps on the dc side for every 100 watts output. I plan to run the wire from the terminal block above the battery back to the kitchen cabinets. From what I can find on line, #8 wire will carry the current, but with the length (around 25 feet) I will be running, I am thinking maybe #6 wire. Any input appreciated.
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Old 03-27-2007, 06:04 AM   #2
ols1932
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#8 wire will more than suffice. According to AWG website, the current rating for copper wire, #8, is 40 amps.

Orv
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Old 03-27-2007, 06:20 AM   #3
Ozz
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I would go with a larger inverter, the start up amps can go as high as 7 times run for a millisecond...depends on the compressor and start assist, if any it has.
I doubt the small one will work. If you have it now, give it a few trys on the old 'bench test'.
Good luck.
Ozz
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Old 03-27-2007, 01:58 PM   #4
Broome101
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You will need 2000 watt inverter to work properly and handle the loads, with a 500 watt you will either trip breaker or circuit if you put one in line or you will burn it up one of the two, agree with Ozz not big enough.
Try this web site will http://www.theinverterstore.com/?gcl...FQfxgAodIDhHRg give you tons of info on them plus help you size for what you are doing.
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Old 03-27-2007, 02:17 PM   #5
boat391
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I'm with Ozz bigger wire is the only way to carry the load also would suggest a transfer switch for when outside power is hooked up I hooked my inverter right through the fuse box to power the 110 plugs I wanted power to works like a charm for my purposes good luck
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Old 03-27-2007, 04:20 PM   #6
SlickWillie
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I am going to wait until I hit the home base and test the freezer then. I am only going to use the inverter strictly for the freezer while on the road. Why would I need a transfer switch, as I will merely plug the freezer into the inverter when we hit the road? Am I missing something there? Thanks for the input.
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Old 03-27-2007, 04:45 PM   #7
richfaa
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Will.. FYI..We have a 3.2 cu ft freezer (Haier) sits in the rear of our 3400 in place of one of the recliners. We keep it at @ Zero degrees. When on the road it remains without power , We have run more than 8 hours and it has warmed only 3 or 4 degrees.You might want to do some testing before spending a lot of money.
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Old 03-27-2007, 04:52 PM   #8
Steve and Brenda
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Wow, this is the classic Edison versus Westinghouse question. The best answer would be to keep the inverter close to the DC power source using a sufficient size wire for the power and then run a 12AWG AC line to the load, in this case the freezer.

Wire length equals current loss in DC circuits. Remember at the turn of the last century AC and DC current went head to head and thankfully AC won or we'd all have to live within a mile of a power generating station just to have sufficient current to run a TV set.
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Old 03-27-2007, 05:23 PM   #9
SlickWillie
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Quote:
quote:Originally posted by Steve and Brenda

Wow, this is the classic Edison versus Westinghouse question. The best answer would be to keep the inverter close to the DC power source using a sufficient size wire for the power and then run a 12AWG AC line to the load, in this case the freezer.

Wire length equals current loss in DC circuits. Remember at the turn of the last century AC and DC current went head to head and thankfully AC won or we'd all have to live within a mile of a power generating station just to have sufficient current to run a TV set.
You make a very valid point. I suppose I could just add another plug in the cabinet. Also, Rich may have the best idea, just close it and leave it alone, unless we decide to boondock a little. You guys are great. That's exactly why I posted. Thanks so much.
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Old 03-27-2007, 07:22 PM   #10
bsmeaton
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Quote:
quote:Originally posted by Steve and Brenda

Wow, this is the classic Edison versus Westinghouse question.
hahaha- great comment Steve! Not sure I would have understood it except I just read the history about it in book a few weeks back.
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Old 03-28-2007, 04:06 PM   #11
Steve and Brenda
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Quote:
quote:Originally posted by bsmeaton

Quote:
quote:Originally posted by Steve and Brenda

Wow, this is the classic Edison versus Westinghouse question.
hahaha- great comment Steve! Not sure I would have understood it except I just read the history about it in book a few weeks back.
Brad, glad you understood. AC versus DC is basic study in the Electronics discipline. You know, most applications use DC still, we just convert the AC to DC INSIDE the device because AC is so easy to move along a power grid.

Willie, what is stopping you from moving to a bigger setup where you can power the entire power grid inside the vehicle with an inverter? You'd have the best of both worlds while traveling. Your batteries would not deplete as long as the TV is running and you have a sufficiently large bank of cells plus you could use the microwave at a rest area!!! Remember the transfer switch - important device when connecting to shore power.
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Old 03-28-2007, 06:00 PM   #12
richfaa
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When we boondock, such as it is, and that has amounted to about 24 hours in Quartzsite, we hook up the old Kipor 3500, crank up the TV, DVD, all the goodies including the freezer..and rough it.
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Old 03-28-2007, 08:48 PM   #13
exav8tr
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Anyone know a good website where I can study up on inverters??? I don't think my '06 3400 has one and would like to explore the possibilities. Also solar energy......
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Old 03-29-2007, 03:50 AM   #14
Ozz
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Look up 'The 12 volt side of life', parts one and two.
I think Glenn has some refrences posted in the home location deal somewhere.
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Old 03-29-2007, 02:25 PM   #15
JH Sechelt
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Hi Phil,

I put a 1200watt Xantrex in, and it runs everything I want it to. ( not always at the same time)
even the drip coffee pot. I put it by the laundry chute.. I don't have to go outside to turn it on & off, and I didn't
need more then the 5' of battery cable they recommend (no longer).
It was also easy to run a extension cord to the entertainment unit in our 2980RL

Heres a website & some pictures.

http://www.xantrex.com/



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Old 03-29-2007, 07:59 PM   #16
Leaseit
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Ok i cheated. Had to break out the ole engineering quick calcualtor i had from the telephone power days. Number 8 AWG (16,510 cm) will carry the load fine. At 25 feet using 8 AWG the voltage drop will be on the order of .17 Volts.

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Old 03-30-2007, 03:28 PM   #17
Steve and Brenda
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In this case current drop is a bigger factor but 8 AWG line feed on a DC circuit is certainly heavier and harder to manage as compared to using 12 AWG load feed from the inverter.
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Old 03-30-2007, 06:29 PM   #18
boat391
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I went to the camping world web site and typed in inverter and found out alot of info I bought the Xantrex 1800 watt with a auto transfer switch built in hooked it up right behind my batts. and ran a remote on and off switch the the cabin right above my tank monitor panel then ran nomex to the circut breaker panel to power the 110 plugs I wanted to use and it works flawless great for those mornings and evenings I want to watch the sat tv without running the gen as to not bother others camping around us we do alot of boondocking so its the perfect fit I also installed 6 12 volt batts. spliting them to two banks useing a batt. A/B switch so I really don't have too much trouble with 12volt power next I will be looking at a solor charger but for now I just run the gen to charge back up
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